Mechanical movement



Dec. 9, 1930.

E. KLAHN MECHANICAL MOVEMENT 4 Sheets-Sheet 1 Filed Feb. 25, 1926 Dec. 9, 1930. E KLAHN 1,784,450

MECHAN I C AL MOVEMENT Filed Feb. 25, 192e 4 Sheets-Sheet 2 'Dec. 9 1930. E. KLAHN MECHANICAL MOVEMENT 4 SheetsSheet 5 Filed Feb. 25. 1926 auveutoz EMU; ELM V,

Z9 i' aa i niimimll w u lilllTmfl 55" Dec. 9, 1930." E, RLAHN 1,784,450

' MECHANICAL MOVEMENT Filed Feb. 25, 1926 4 Sheets-Shet 4 Patented Dec. 9, 1930 PAT ENT OFFICE EMIL K LAHN, OF NEW VERNON, NEW JERSEY MECHANICAL MOVEMENT r Application. filed *February 25, 1926. Serial No. 90,521.

This invention relates to a new mechanical movement, the same being especially adapted for automatic and manually operated electric'switch mechanism, and also being capa- 5 ble of application for a wide variety of mechanical and electrical instruments and apparatus wherein an element having a snap action is desirable and in many cases essential.

Among the objects of my invention are the provision of a mechanism of the above character which is simple in construction and con sequently easy of assembly, is capable of successful operation for prolonged'periods of time With certainty and regularity and does not necessitate the employment of rare metal contact members when employed in many of the types -.of electrical instruments or apparatus for which it is especially adapted, is relatively cheap -to manufacture and withal is highly durable even under severe conditions of operation. 1

In the accompanying drawings-forming a part of this specification, I have illustrated 5 certain preferred embodiments of my invention comprising thermostatic key-operated switches, although I do not thereby intend to restrict the same only to such embodiments without departing from the essential principle which I have discovered and have disclosed herein. g 1

Referring to the drawings,'Figure 1 is a front elevation of a thermostatic switch embodying my invention in a make or closed position in which the heat responsive arms are adapted to exert an inwardly direct pressure when. heated and vice versa when cooled;

Fig. 2 is a vertical section on the line 22 of Fig. 1, except that the position of the lead wires is changed;

Fig. 3 is a similar elevation to that shown in Fig. 1, the switch being shown open;

Fig. 4 is a longitudinal perspective of the spring element of the switch, isolated;

Fig. 5 is a plan view, from above, of the switch shown in Fig. 1, the lead being omitted;

Fig. 6 is a front elevation, in a make position, of a modified form of thermostatic as the invention is capable of many variations switch and Fig. 7 is a vertical section on the line 77 of Fig. 6;

Fig. 8 is a longitudinal perspective of a modified form of spring element, isolated;

Fig. 9 is a front elevation of still another modification in which the heat responsive arms are adapted to exert an outward pull on the spring element when heated and vice versa when cooled, the same being shown in full lines in a make or closed position and in dotted lines in a break or open position;

Fig. 10 is a vertical section on the line 1010 of Fig. 9 and Fig. 11 is a section on ilshe median line of the bracket 20 shown ing 5 Fig. 12 is a fragmentary front elevation of certain switch elements shown in Fig. 9, isolated, but showing the contact members in a break or open position;

F ig.l3 is an elevation and Fig. 14 a fragmentary detail elevation partially in section of a further form of switch;

Fig. 15 is an elevation, partially in section, of another modification and Fig. 16 is a perspective detailview of the washer elements thereof; i

Fig. 17 is a front elevation and Fig. 18 is an end elevation of a lamp socket embodying a' form of my invention;

Figs. 19 and 20 are sections on the line 19-19 of Fig. 17 showing closed and open positions of the switch embodying a normally sprung or deformed snapping element.

Fig. 21 is an enlarged fragmentary perspective view of a portion detail of such mechanism;

Fig. 22 is a perspective View of the cam element isolated and Fig. 23 is a perspective view of the key element.

Referring to Figs. 1 to 5 of the drawings, the reference numeral 1 designates a bracket to each of the upturned ends of which are riveted or otherwise rigidly connected, twin heat-responsive arms, 2, 2 of so-called thermostatic metal, preferably comprising strips of dissimilar metallic material as inner strips of steel 3, 3' of a very low index of expansion, and outer str ps of brass, the latter being a metal having an extremely high index of expansion. An upright bracket 4:is riveted or otherwise rigidly secured to the central portion of the bracket 1, the two brackets 1 and 4: 5 being completely insulated from each other in any suitable manner, preferably by interposed strips of insulating material 5 in the well known manner. Binding posts 6, 6' are provided on the respective bracket members, the same affording means for connecting leads 7, 7 of insulated wire to such brackets.

The binding post 6 is provided with a contact tip piece a of platinum, for example, though the same may be formed of rare metal alloy as platinum-iridium, etc. if desired.

The upper ends'of the heat-responsive arms are slotted as indicated by the reference letters b, b to receive the reduced ends 0, 0 respectively of a snapping bow member 8 0 composed preferably of highly tempered spring steel as for example, of a grade commonly employed for clock springs. .As shown in Fig. 4, this member 8 is preferably arched so thatnormally when isolated it assumes. the form of an upwardly arched bow though the same may be crimped at the center as shown in Fig. 8 as hereinafter described. The length of the member 8, exclusive of its reduced ends, is preferably greater .30 than the distance, at normal temperature, be-

tween the heat responsive arms at the level of the slots or apertures b, b and consequently when the member 8 is mounted in the slots 6, 6 its natural tendency, if unobstructed,

.35 will be to assume an upwardly arched position as indicated by the dotted line position shown in Fig. 1. However, the binding post 6 is soadjusted that instead of the spring being allowed to assume an upwardly arched position, it will be normally held in the position shown in full lines in Figs. 1 and 2 in which position, as will be observed, the center of the spring 8 will lie somewhat below the level of the apertures b, 1) into which the ends 0, a of the spring project. As a consequence, when the instrument is cold or at a temperature below that at which it is adjusted to operate, intimate and perfect engagement will be insured between the contact a and the snapping spring member 8 until the very instant of their snapping separation since not only is the spring, because of its natural arch, normally held in snug engagement with the contact a, but as the inwardly directed pressure of the free ends of the heat-responsive arms increases due to the increase in temperature of such arms, the spring isinitially forced with" greater pressure even greater than its normal pres- 0 sure against the contact a and then suddenly as the pressure on the ends of the spring increases, said spring is caused to snap away from the contact a assuming the spring or break position shown in Fig. 3.

As the heat-responsive arms cool down, the

inwardly directed pressure decreases gradually and spring 8 gradually moves back to a position intermediate the positions shown in full lines in Figs. 1 and 3, say to a position as illustrated in dotted lines in Fig. 3 and from that position as the arms cool further the spring 8 suddenly snapsinto engagement with the contact a.

In Figs. 6, 7 and 8 I have illustrated a modified form of switch in which a single heat-responsive member 10 is mounted upon and insulated from a bracket 11 by means of one of a pair of binding posts 12, 12. Terminal arms 13, 13 are riveted to the free ends of the heat-responsive member 10 and said armsin turn support a spring member 14 which, as previously stated, is crimped to form a central rib (Z. In this construction the steel or non-expansive component 15 of the thermostatic member is also on the inside and the brass or like highly expansive component is on the outside, hence the operation of this modification of thermostatic switch is in all its essential aspects similar to that shown in Figs. 1 to 5 inclusive.

In the construction shown in Figs. 9 to 12 is illustrated a modification in which a bracket 20 carries heat-responsive arms 21, 21 that are formed with the expansive component 22 on the inside and the steel or steel component or strip of relatively non-expansive metal on the outside whereby the movement of such arms under, the influence of heat is exactly the reverse of the construction shown in Figs. 1 to 5 or 6 to 8.

The spring member 23 carries a centrally mounted wedge-shaped contact member 24 which is adapted to co-operate with U- shaped socket members 25 having spaced spring jaws 25', 25", that are mounted on the end of a leaf spring 26 anchored, as shown in arm 27 of a supplemental bracket 28 which is carried by and insulated from an upright bracket 20. The contact member 25, which is preferably of phosphor bronze, has opposing projecting integral spring arms e, e and these arms normally engage the front and rear edges of an aperture f formed in the top 28 of said bracket 28, said aperture being of greater extent from front to rear than the opposing members 25, 25" when in their spread position.

Projecting. outwardly from bracket 28 is an integral U-shaped stop member comprising an upper apertured plate 29 through which the lower end of the socket member 25 permanently projects and a lower plate 30 serves to limit the extent ofmovement of the reciprocating jaw member 25.

The different positions of the switch elements during the operation thereof under the influence of heat and upon the subsequent cooling-thereof are successively illustrated in Figs. 9 to 1.2. In the full line position shown in Figs. 9 and 10, the switch elements 24 doubled with the resultant diminution of and 25" are shown in engagement due to the arms 21, 21 being in their normal or cold position. Upon the heating of the arms 21, 21 the same gradually expand or spread until they attain the dotted line position shown in Fig. 9. During this movement of the arms the jaws 25', 25", are dragged upward by the initial gradual upward movement of the snapping element 23 and the tooth 24 carried thereby. As the spring element 23 passes the dead line or critical intermediate position thereof which is substantially that shown in full lines in Fig. 11, the wedge element will suddenly snap away from the jaws 25, 25 and as the latter seeks to follow the same, the end of spring 26 strikes the stop 29 which prevents further upward follow of the jaws 25, 25"

and the latter now being subject only to action of the spring 26, thereupon snap downwardly into their normal or lowermost position-shown in Figs. 10 and 12. As a consequence of the sudden movement in opposite directions, the speed of separation of the respective switch members is practically the are formed to a minimum. Furthermore,

wiping engagement of the .wedge 24 with theoutwardly flaring tips of the arms 25', 25" insures the maintenance of the contracting surfaces of the switch elements in a clean condition and reduces the possibility 21' are subjected to heat, occurs.

ofcorrosion to a minimum.

-Upon cooling, the reverse action to that above described, when the contact arms 21, As the arms 21, 21 slowly contract or approach each other, the spring 23 and its tooth 24 suddenly snap from the dotted line position shown in Figs. 9 and 11 and the full line position shown in Fig. 12 into the full line position shown in Figs. 9 and 10 and snaps into engagement with the jaws 25, 25.

7 Due to wiping action obtained by the employment of the knife type of switch shown in Figs. 9 to 12, it is possible to employand construct the wedge 24 and the coacting arms 25', 25" of base metal, such as copper, silver etc. in lieuof rare metal contacts. Furthermore, in order to facilitate the. separation of the contacting ends of the.jaws 25, 25" when the' wedge 24 is thrust therebetween, .the lower edge of the wedge is preferably cut sloping so that it enters progressively along its edge into contact with. the jaw 25, 25".

As shown, the lead wires are connected respectively to the bracket 20 and the arm 27.

In Figs. 13 and 14, I have illustrated a modification 'whereinthe thermostatic arms are adjustable and both a positive and negative make and break is obtained in the circuitf In this construction a bracket 35 is provided with integral bosses or hubs 36 which latter are securely held in any desired position of adjustment in said bearings by means of lock nuts 38.

Heat responsive, bi-metallic arms 39 are anchored in slots 40 formed in said stud shaft, the same being rigidly secured by means of set screws 41.- The upper ends of these arms are provided with slots 42 similar to those shown in Fig. 14. A snapping spring element 43 is mounted in said slots 42, the same being arched and this arch is flattened out when the element is mounted so as to unbalance or arch the same and cause it to normally seek the position shown in Fig. 13 when the thermostatic arms 39 are at normal temperature. Said spring carries a wedge contact member 44 electrically separated therefrom by insulation 45.

A vertical arm orbra-cket 46, rigidly secured by rivets or otherwise to the bracket 35, is provided with an offset end 47 that serves as a support for a screw-top 48 which in turn is locked in any desired adjusted position by a nut 49.

A supplemental bracket 50 is rigidly Secured to said arm 46 and is iniurn separated therefrom by insulation 51. On said top 52 of leads are cpmposed of high resistance wires,

such-as for example, as used in an electrical cigar lighterand each arm 39 is Wrapped with a predetermined and equal number of coils of this ire so as to insure that the heating up of'these arms will occur in a predetermined interval of time. Between the source of electrical supply and the wire wrapped on each thermostatic arm 39, is interposed a 25. watt resistance coil, as indicated in the drawings, in

order to protect the delicate high resistance wiring on these arms. If the thickness and selected with respect to the resistance wrapped around the same, it is possible, in the construction shown in Fig. 13, to obtain an interval of heating and cooling of the arms with the consequent interval of operation of the switch which is substantially uniform and even, for example, an interval between operations of the switch of 3 seconds for many purposes would be highly desirable and when using bimetallic tremostatic metal arms having a total thickness of 0.020" for the combined thickness of the two metals composing said arms, it is possible with the ordinary resistance used in an electrical cigar lighter to wrap the proper number of turns on said arms length ofthe thermostatic arms are properly 1 to obtain this particular interval of operation, Without using additional resistances.

In Figs. 15 and 16 a modified form of snapping element is illustrated. In this construction, a normally flat spring 60 (see dot and dash line Fig. 15).is permanently arched by mounting the same between washers or blocks 61 and 62 respectively, the same havinga concave face 61' and a convex face 62. These blocks are secured together by means of a bolt 63 threaded into a wedge shaped tooth 65 and is provided on its opposite end with a nut 64 that serves to lock said tooth 64 and said blocks'61 and 62 and said spring 60 together and hold said spring in the arched position shown in full lines in Fig. 15. The ends of said spring which are not illustrated in Fig. 15 are, of course, similar to the ends of the spring shown in Fig. 13 and are mounted on the arms 39 in a similar manner to that shown in Fig. 14.

The operation of the construction shown in Figs. 13 to 16 inclusive is in all respects essentially the same as that shown in Fig. 9 insofar as the movement of the tooth and spring which carries the same is concerned. The construction shown in Figs. 15 and 16 merely shows the construction by which the permanent arching, when isolated, of the spring element, is obtained and yet without the necessity for the actual deformation of the spring so that it is slighly arched or deformed as shown in Figs. 1 and 8, thus insuring more uniform results than is otherwise possible with the pre-deformation of the spring. v

The adjustment of the heat responsive arms of the construction shown in Figs. 13 and 14 is, of course, accomplished merely by loosening the nut 38, then inserting a screw driver or other tool into the groove 9 of the journal 37' and moving arms to the desired adjusted position at which the locknut 38 is screwed down tight.

In the lamp socket switch shown in Figs. 17 to 23 inclusive, the reference numeral 7O designates an insulation base and 71 a U-shaped bracket, secured thereto by screw bolts 72,

which supports the lamp socket proper orterminal 73, being secured thereto by bolts 7.4.

Asecond bracket 75 having an offset foot or lugj75 serves as the other terminal of the socket. A second lug 76 is secured to the insulation base 70 by a bolt 7 7 and said lugs each support spaced jaw stop members 78, 78 respectively of a knife or blade switch which are as shown integral with the lateral arms or members 79. 7 9' struck up from the lugs 7 5 and 76. Insulated leads 80, 80 connect'the lugs 7 5', 76 to opposite terminals of a source of electrical current for operating the lamp as for example a 120 volt direct current or a 60 cycle 110 volt alternating current. (To avoid confusion these leads have been I shown in Fig. 18 as extending at right angles to the position of the leads illustrated in Figs. 17, 19' and 20.)

A spring metal bracket or support 81, preferably U-shaped, and having opposing arms 82, 82 is also secured, by means of its integral foot 83 and bolt 84, to the base 70. Said latter bracket normally compresses the snapping switch element 85 which is formed at its center into a tongue 86, having a slotted aperture, that is adapted to assume two positions of rest as illustrated more particularly in Figs. 19 and20, viz: a make and a break position with respect to the co-operating jaws 78 and 7 8' The element 85 is provided at each end with a pair of terminal lugs 87 that are adapted to loosely fit in marginal recesses Z of the arms 82, 82 so as to al- 7 low slight to and fro movement of the ends 87 with respect to the arms 82, 82 during the snapping movements of the tongue member into and out of the jaws 78, 78' whereby the setting up of undue compression strains orstresses in the ends of the arms 85 with greater likelihood of crystallization of the spring metal adjacent the points of support are minimized.

A key or shaft 88 projects through the slot 86' and is mounted in the opposing apertures m provided in each of the arms 82, 82' and a washer 89 is interposed between said arm 82 and the knob 90 to facilitate the turning of the key when desired without undue friction. As shown the one end of the key 88 is flattened and split to form lugs 91 and the aperture m is expanded as indicated by the reference letters m to admit of the passage therethrough of said flattened end during assembly and prior to upsetting the lug 91. A cup shaped element 92, having upturned cam ends 93 which project at angles of about 45 therefrom, is adapted to be rigidly keyed on' the flattened end of the key 88 with said cam ends projecting inwardly when the said flattened end is inserted through the co-operating slot 9 in which it snugly fits and the lugs 91 are oppositely upset, as shown more especially in Fig. 18.

The operation of said switch is accomplished, as is customary in switches of this general type by merely rotating the knob 90 (which is preferably molded on the other flattened end of the key 88) in either direction whereupon a snapping action of the switch will cause the tongue 86 to assume either the make position (see Fig. 19) or the break position (see Fig. 20) depending on the position of rest before the knob was rotated. Such snapping action is due to the compression or expansion. of the arms 82, 82' under the influence of the camsurfaces 93 as they move from one position of rest tcp another e. when the cam surfaces are ,turned from the position shown in Fig. 19 to that shown in Fig. 20, the arms 82, 82 will be caused to move from an expanded position to a compression position and vice versa when the such cam surfaces are moved from the position shown in Fig. 20 tothat shown in Fig. 19.

In lieu of a separate cam element 92 (see Figs. 17-20), the shank 88 of the key may consist of a cotter pin and its free ends may be oppositely upset to form integral cam faces somewhat corresponding to the ends 93.

I, much prefer to construct the snapping element as a separate part of the mechanism from the compressible anchorage arms and to mount said element in said arms so that the longitudinal axis of the ends can move (as illustrated in Figs. 1, 9 and 13) in a plane including such axis and the longitudinal axis of the anchorage arms during the snappingjaction of the central portion of the snapping element; Thereby undue stresses upon the ends of the snapping element are avoided and undue crystallization or molecular rearrangement is avoided to a maximum degree, thus preventing breakage of the snapping element at the anchorages thereof. However, I may rigidly anchor the snapping element in its anchorages or when the anchorages are of similar metal, as for example in the construction shown in Figs. 17 to 21, the snapping element may be formed integral with said anchorages if desired,

though this will tend to increase the likelihood of crystallization of the snapping element at its points of juncture with the cooperating compression arms.

The novel mechanism herein described is,- of course, capable of a wide variety of uses wherein itserves to replace other less effective and more complicated mechanism, for exama simple construction, for use in thermostaticple it is not onlycapable of replacing the slow-moving, often unreliable, thermostatic devices now employed in various electrical implements and instruments, but it is adapted for use as a time-relay device in railway signalling, electric signs, electro-plating and other electrochemical operations and also forvarious mechanical devices wherein a snapping action is essential, and where more complicated mechanism would otherwise be rel quired, It is peculiarly adapted, because of its certainty of operation and its sturdy and electric sad irons which, as is wellknown, are subjected to, relatively rough usage as compared with -many other electrical devices wherein thermostats have been employed to control the temperature thereof. Furthermore, said mechanism lends itself, because of its powerful positive action, for employment in the operation of train control trip mechanism, either with or without association with simple electro magnets in lieu of the more expensive motors and compressed air mechanism and complicated electromagneticdevices now commonly employed as theactuating mechanism for such trips. J

While I have illustrated several preferred embodiments of my invention, I do not intend thereby to restrict myselfthereto, nor to the details of construction thereof, except insofar as the same are. limited by the scope of such claims as may ultimately be granted in any patent issuing upon this application or any division thereof.

The spring member-shown in the different modifications herein disclosed, for example, the members 8, 14, 23, 43, 60 and comprise membranes of spring metal i. e., flat ribbons or sheets thereof, but other snappingreciprocatory elements adapted to vibrate transversely of their longitudinal axis are equally within the scope of certain of the appended claims.

Having thus described my inventlon, what I claim and desire to obtain by United States snapping element from assuming a sprung position equi;distant from a neutral center line with the other sprung position, means for effecting the relative movement of said arms with respect to eachother and a pair of contact terminals adapted to be respectively connected to a source of electricity and normally insulatedfrom each other when the circuit is'open adapted to make and break by the movement of said snapping element from one position of rest tov another.

2. A thermostatic knife switch comprising a supporting bracket, a snapping circuit closer element having its ends loosely anchored in opposing relatively movable supports, a portion of which latter being rigidly secured to said bracket, a pair of co-operating terminals connected to said bracket and normally insulated from each other when the switch is open, one of said terminals comprising a blade and the other a pair of aws, said jaws being capable of slowlyv following the blade during the initial movement thereof said snapping element passing through a neutral state and thereby insuring that said element will be in a live position at all times and co-operating contacts arranged to have snapping make and break in unison with the snappmg movementsof the snapping element.

4:. In a switch, the combination comprising a frame, insulated opposing relatively movable contact members carried thereby, means for connecting said contacts toa source of electricity, a snapping element adapted to effect snapping make and break of the contacts, a stop member carried by said frame, for preventing said snapping element crossing a rectilineal line drawn between its ends during the operations thereof and relatively movable arms rigidly secured to said support and serving as anchorages for the respective ends of the snapping element, said arms being adapted at times during the operation of said switch to be moved toward each other and exert an endwise pressure on said snapping element suflicient to cause the latter to snap into a different position from the position assumed when said arms are at their extreme positions of separation.

5. A thermostatic switch including spaced supporting arms of bi-metallic thermostatic metal hav1ng a snapping element spanning the space intermediate said arms and mounted by its respective ends on said arms, said snapping element being deformed so that its longitudinal axis will normally lie to one side of a straight line drawn between its respective ends if the latter are unconfined, a stop toprevent the snapping element coming to rest at'and beyond a dead center position and co-operating contacts insulated from each other and arranged to snap into and out of engagement in synchronism with the movements of said snapping element.

6. In a switch, the sub-combination comprising a spring metal bridge member, confining anchorages therefor capable of toand fro movement with respect to each other, said bridge member being deformed so that, if relieved from the pressure of its anchorages, its longitudinal, axis will lie to one side of a straight line drawn between its ends and a stop for preventing said bridge member from assuming a configuration corresponding to the deformed configuration it would assume if its ends were unconfined.

7. A knife switch having snapping make and break actions, and including a compressible, elastic, reciprocatory normally rectilineal membrane element and separate deforming means secured centrally thereto. v

8. A thermostatic knife switch having snapping make and break actions and the same including a normally rectilineal membrane element of spring metal having separate deforming means secured thereto.

an electric switch mechanism, the

combination comprising supporting means, a spring metal snapping membrane member bridging portions of said supporting means, said membrane member being, if isolated, normally straight and means secured to said membrane element substantially distant from the ends thereof, adapted to deform said membrane element out of a straight line drawn between its respective ends and cooperatin contact elements, one of said elements being'carried by said membrane member and arranged to snap into and out ofren- .gagement with the other in synchronism with the movements of said snapping element.

10. In a switch, the sub-combination comprising a spring-metal snapping membrane, the same being mounted at its respective ends in opposing supports, said membrane element being normally straight, if isolated, and having co-operating male and female deforming means secured to the opposite sides respectively of said membrane at a point distant from the ends thereof and adapted to permanently deform said membrane from a straight line drawn between its ends.

11. A snapping member for a thermostatic switch, comprising a band-like spring-metal snapping membrane, the same being normally straight, if isolated and having. opposing deforming means secured to opposite sides thereof to effect permanent distortion of said snapping member throughout the period that the same is associated with said deforming means. k

12. A snapping member for a thermostatic switch, comprising a spring-metal snapping membrane, deforming means substantially centrally disposed with respect to the ends of said snapping element and secured thereto 1n such a anner as to effect permanent distortion of said snapping member with respect to its normal configuration throughout the period that the same is associated with said deforming means.

13. In a snapping switch, the combination comprising an elastic snapping element,

means for supporting the same and deforming means secured to said snapping element and normally adapted to deform the same from the natural position which would otherwise be assumed thereby, if isolated.

14. In a thermostatic switch, the combination comprising a composite thermostatic element, a snapping element associated therewith and a clamping device secured to said snapping element to effect a permanent dis tortion thereof with respect to the natural shape of the element when isolated therefrom.

15. In a switch, the combination comprising heat-responsive means including a normally straight snapping element adapted to assume two different positions constituting cold and hot positions respectively and separate means secured to said snapping element,

' ping member substantially distant from its ends for efiecting the distortion thereof from its normal median or axial line.

16. In a thermostatic switch, the combination comprising a support, a plurality of thermostatic arms-mounted thereon, a snapping element spanning the space between said thermostatic arms and carried thereby, a plurality of contact members, one of which includes a pair of elastically mounted jaws connected to a source of electrical supply, adapted to abruptly snap into and out of engagement with each other consonance with the movements of said snapping element, said jaws'being arranged to cooperate with the snapping element and prevent the initial separation of said contacts until suflicient energy has been. stored up in said'snapping element to cause theabrupt separation there-- of from said jaws.

17 In a switch, the subcombination comprising a snapping element, supporting means therefor, said snapping member substantially distant from the'ends thereof and causing said snapping member'to assume a different configuration from that which it normally assumes if isolated from such deforming means.

18. Ina thermostatic switch mechanism, the combination comprising supporting means, a snapping member secured thereto and deforming means secured to saidsnap- 1 and substantially centrally thereof, said deforming means serving to hold said snapping member 1n a deformed position With respect to the normal position thereof when isolated I from said deformin means.

Signed at New Iork, in the count and State of New York, this 20th day of l ebruary, 1926. E

- MIL KLAHN.

deforming means secured to intermediate the ends thereof 

